Air spring with debris and ice barrier

ABSTRACT

An air spring including a spring seat, and a flexible sleeve connected to the spring seat. The flexible sleeve forms a compression chamber and includes a lobe that rolls along a surface of the spring seat during compression of the flexible sleeve. An annular barrier is disposed on the spring seat between the lobe of the flexible sleeve and the surface of the spring seat to deflect debris and ice from becoming lodged or trapped in the spring seat that may damage the flexible sleeve.

FIELD

The present disclosure relates to an air spring including an annularbarrier for deflecting debris and ice.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Air springs are commonly used for motor vehicles, various machines, andother equipment. The springs are designed to support a suspension load.The springs are often combined with a separate shock absorber device inthe suspension that functions to dampen oscillations. Air springsgenerally consist of a flexible elastomeric reinforced sleeve thatextends between a pair of end members. The sleeve is attached to the endmembers to form a pressurized chamber therein.

During operation of the air spring, the flexible sleeve will compress toadjust a volume of the pressurized chamber. To accommodate this flexing,the sleeve will form lobes as the sleeve is compressed that roll alongsurfaces of the end members. If any debris is present between the endmembers and lobes, however, the sleeve may become damaged, which willshorten its useful life, as well as reduce the efficiency of the airspring. To solve this problem, it is known to completely enclose the airspring with a protective shield. The use of this protective shield,however, is undesirable in that it adds undesirable weight to the airspring and, therefore, the vehicle. Further, the protective shield addsto the manufacturing costs of the air spring. Accordingly, there is aneed for an improved air spring that prevents debris and ice frombecoming lodged between the lobes of the elastomeric sleeve and endmembers.

SUMMARY

With the above need in mind, the present teachings provide an air springincluding a spring seat, and a flexible sleeve connected to the springseat. The flexible sleeve forms a compression chamber and includes alobe that rolls along a surface of the spring seat during compression ofthe flexible sleeve. An annular barrier is disposed on the spring seatbetween the lobe of the flexible sleeve and the surface of the springseat to deflect debris and ice from becoming lodged or trapped in thespring seat that may damage the flexible sleeve.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a cross-sectional view of an air spring according to thepresent teachings;

FIG. 2 is a cross-sectional view of an air spring according to thepresent teachings;

FIG. 3 is a cross-sectional view of the air spring of FIG. 2 in acompressed state;

FIG. 4 is a cross-sectional view of a prior art air spring;

FIG. 5 is a cross-sectional view of the prior art air spring of FIG. 4in a compressed state; and

FIG. 6 is a cross-sectional view of an air spring according to thepresent teachings.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

Referring to FIGS. 1-3, the air spring device of the present teachingswill now be described. As shown in the figures, the air spring device 10generally includes an upper spring seat 12 and a lower spring seat 14.Connecting the upper seat 12 and a lower spring seat 14 is a flexiblesleeve 16 that forms a compression chamber 30.

The upper spring seat 12 generally includes an upper cap member 18 thatsupports a piston 20. Also connected to the upper spring seat 12 andsurrounding the piston 20 is a cylindrical shield 23 that protects thepiston 20 from being damaged by debris. Lower spring seat 14 includes aprotective collar 22 and a connection member 24. The sleeve 16 isconnected to the piston 20 and the connection member 24 by clampingrings 26. The sleeve is generally elastomeric or composite in nature. Ifelastomeric, the sleeve 16 may have cords embedded in the elastomericbody. If composite, the sleeve may have a first flexible memberconnected in a partially overlapping manner to a second flexible member.Regardless, any type of sleeve known to one skilled in the art may beused with the present teachings, without limitation.

During operation of the air spring, the sleeve 16 will compress andlobes 27 and 28 of the sleeve 16 will roll along surfaces of the piston20 and the lower spring seat 14, respectively. Specifically, the lobes27 of the sleeve 16 connected to the piston 20 will roll along an outersurface 21 of the piston 20, and lobes 28 of the sleeve 16 attached tothe connection member 24 will roll along and be supported by theprotective collar 22. In this manner, air or fluid within chamber 30will increase and decrease according to a volume of the chamber 30 thatis contingent upon flexing of the sleeve 16. Air that is in the chamber30 may enter and be disposed of through a conduit 32 which is an axiallydisposed bore that travels through the piston 20. At a portion of theconduit 32 that is adjacent the chamber 30 is disposed a plug 34. Theplug 34 can open and shut during vibrations experienced by the airspring 10.

In accordance with the present teachings, and as best shown in FIGS. 1and 2, the air spring 10 of the present teachings includes an annularbarrier or seal 36 which is disposed in the lower spring seat 14. Theannular seal 36 is preferably comprised of a flexible polymer or thermalplastic elastomer. In this manner, the annular ring 36 is compressible(FIG. 3). Materials that may be used to form the annular seal 36 includenatural rubber, SBR, butadiene blends, nitrile, neoprene,polychloroprene, urethanes, EPDM, and combinations thereof. Preferably,these materials form closed-cell foams to prevent the annular seal 36from absorbing any moisture that the air spring 10 is exposed to, butthe present teachings are also adaptable to open-celled foams. If anopen-celled foam is used, a coating of another material should be formedto cover the open cells of the foam to prevent or at least substantiallyminimize the absorption of water by the annular seal 36. Regardless whatmaterial is chosen for the annular seal 36, the material should becompressible to accommodate the rolling lobes 28 of the sleeve 16 whenthe air spring 10 is compressed.

To manufacture the annular seal 36, any method known to one skilled inthe art may be used. In this regard, the annular seal 36 is preferablyformed by injection molding or compaction molding. Other methods includeusing a water-jet to cut and form the annular seal 36, as well asextrusion molding. Regardless, any method proficient at producing theannular seal 36 may be used.

According to the present teachings, the material should be selected suchthat the annular seal 36 is proficient at preventing debris and ice thatthe air spring device 10 may be exposed to during operating conditionsfrom becoming trapped in the lower spring seat 14. More specifically,referring to FIGS. 2, 4, and 5, the air spring 10 will be exposed todebris and ice during operation of the motor vehicle. Without theannular seal 36, the debris or ice 38 may become lodged or trapped bythe protective collar 22 (FIG. 4). If the debris or ice 38 becomestrapped in the protective collar 22, it may damage or crimp the sleeve16 when the sleeve 16 compresses and the lobes 28 roll along the surfaceof the collar 22. This is undesirable because the useful life of thesleeve 16 may be shortened, as well as the efficiency of the air spring10 will be reduced if holes or tears develop in the sleeve 16.

Now referring to FIG. 2, it can be seen that by disposing the annularseal 36 in the lower spring seat 14 the debris 38 is prevented frombecoming lodged or trapped within the lower spring seat 14 because theseal 36 acts as a barrier that prevents the debris or ice 38 fromentering the protective collar 22. In other words, the debris 38 isdeflected by the annular ring 36. Accordingly, damage to the sleeve 16can be prevented or at least substantially minimized.

During compression of the air spring device 10, the annular ring 36, asstated above, is formed of a compressible material. In this regard,during compression of the spring 16, as shown in FIG. 3, it can be seenthat the compressible material of the annular ring 36 will compress suchthat it does not inhibit a rolling motion of the lobe 28 through theprotective collar 22 of the lower spring seat 14. In this manner, theair spring device 10 is allowed to operate as designed. Upondecompression of the air spring 10 and sleeve 16, the annular seal 36will return to its original form. In this manner, the annular seal 36continually fills the space between the lobe 28 of the sleeve 16 and theprotective collar 22 to prevent, or at least substantially minimize, theintrusion of debris and ice in the protective collar 22. Furthermore,the spring or bellow 16 is prevented from becoming damaged by any debriswhich may become lodged in a lower spring seat 14. Accordingly, theuseful life of the air spring device 10 and the sleeve 16 is increased.

Although the above embodiments describe a configuration where theannular barrier 36 is disposed in the lower spring seat 14, it should beunderstood that the present teachings should not be limited thereto.That is, referring to FIG. 6, the air spring 1 0 of the presentteachings may also include an annular barrier 40 disposed within theupper spring seat 12 as well. In this manner, the need for theprotective shield 23 can be eliminated. Accordingly, debris may also beprevented, or least substantially minimized, from becoming lodged ortrapped in the upper spring seat 12. What's more, the weight of the airspring 10 can be further reduced by removing the need for the protectiveshield 23.

The description of the present teachings is merely exemplary in natureand, thus, variations that do not depart from the gist of the presentteachings are intended to be within the scope of the present teachings.Such variations are not to be regarded as a departure from the spiritand scope of the present teachings.

1. An air spring comprising: a spring seat including an annular axiallyextending collar; a flexible sleeve connected to said spring seat, saidflexible sleeve forming a compression chamber and including a lobe thatrolls along a surface of said spring seat during compression of saidflexible sleeve; and an annular compressible barrier disposed on saidspring seat between said lobe of said flexible sleeve and said annularaxially extending collar, wherein said barrier is adapted to compress assaid lobe rolls along said surface of said spring seat and is adapted todeflect debris from said spring seat. 2-4. (canceled)
 5. The air springof claim 1, wherein said barrier is formed of a material selected fromthe group consisting of natural rubber, SBR, butadiene blends, nitrile,neoprene, polychloroprene, urethanes, EPDM, and combinations thereof. 6.The air spring of claim 1, wherein said barrier is resistant to water.7-13. (canceled)
 14. An air spring comprising: an upper spring seat,said upper spring seat supporting a piston; a lower spring seatincluding a protective collar; a flexible sleeve connecting said pistonand said lower spring seat, said flexible sleeve forming a compressionchamber and including lobes that roll along surfaces of said piston andsaid lower spring seat during compression of said flexible sleeve; and acompressible annular barrier disposed within said protective collar,said annular barrier adapted to compress when said lobe of said flexiblesleeve rolls along said lower spring seat, and adapted to deflect debrisfrom entering said protective collar.
 15. The air spring of claim 14,wherein said annular barrier is formed of a material selected from thegroup consisting of natural rubber, SBR, butadiene blends, nitrile,neoprene, polychloroprene, urethanes, EPDM, and combinations thereof.16. The air spring of claim 14, wherein said annular barrier is formedof an open-celled foam.
 17. The air spring of claim 16, wherein saidannular barrier includes a coating.
 18. The air spring of claim 14,wherein said annular barrier is formed of a closed-cell foam.
 19. Theair spring of claim 14, wherein said annular barrier is resistant towater.
 20. The air spring of claim 14, further comprising anotherannular barrier disposed within said upper spring seat, said anotherannular barrier adapted to compress when said lobe of said flexiblesleeve rolls along said surface of said piston, and adapted to deflectdebris from entering said upper spring seat.